Pelican hook for ratchet couplings



Aug. 28, 1962 R. H. KERNAHAN 3,050,300

PELICAN 500K FOR RATCHET COUPLINGS Filed June 21, 1961 INVENTOR. RICHARD H. KERNAHAN United States Patent Filed June 21, 1961, Ser. No. 118,691 15 Qlaims. (Cl. 24-6Q) This invention relates generally to ratchet coupling mechanisms andm'ore particularly to an improvement in the lock and link mechanism of tension exerting couplings of the kind commonly known as steamboat or tugboat ratchets, and especially to the pelican hooks for such ratchet couplings.

Ratchets of the aforementioned type are commonly used on the Ohio and Mississippi rivers for coupling a plurality of barges into a unitary train to be towed. Normally, such barge trains may comprise up to 20 barges which, according to size, may be arranged from two to four abreast and with as many as ten from end-to-end. A single tugboat is coupled to the rear of the train of barges to push the entire train which may be as long as 1000 feet or more.

In order to maneuver a barge train of this type and size, it is necessary for each barge to be tightly coupled to the adjacent barges at the sides, front and rear so that the entire train is relatively rigid and extends rigidly forward of the tugboat so that it may be guided thereby. Such a barge train is subject to sudden and strong forces due to cross currents and winds, and it is accordingly necessary to utilize a strong tug having as many as three rudders operated by 100 HP. motors.

i A ratchet link mechanism for rigidly tensioning and tying the barges together in such trains is disclosed in Patents No. 1,971,472 issued August 28, 1934 to C. Wolf and No. 2,198,181, issued April 23, 1 940 to G. I. Rumpler. The disclosed device comprises reversely threaded bolts actuated in opposite directions by means of a turnbuckle member. with a ratchet fixed thereto and having a suitable lever pivotally mounted thereon and carrying a reversible pawl engageable with the turnbuckle ratchet, with a chain or loop engaging coupling, commonly called a pelican hook, connected with each bolt. Mechanisms as disclosed in this patent, or similar ones, although suitable as couplings for the purpose described, the pelican hooks associated therewith are subject to a number of disadvantages.

When it becomes necessary to uncouple one or more barges from the train, these link mechanisms, and particularly the known types of pelican hooks, are difiicult to unlock. It is usually necessary to lessen the tension in the coupling between two barges by operating the ratchet, but even then the lock arm of the pelican hook is still under considerable force and it is necessary to strike the keeper links with a sledge hammer or the like to unlock the coupling. This operation is not only difficult under the best of conditions, but is also dangerous to the operators when it must be performed in the dark and/or during inclement weather. Another difficulty with the known pelican hook structures is that under the sudden changes of stress from cross currents or the like, the strain between barges may suddenly he reduced and with the designs of such mechanisms, it is possible for the coupling elements or pelican hooks to he suddenly rearranged into positions in which a keeper link can accidentally fall away and thus uncouple and release a barge during a period when maneuverability and control of the train is most difficult.

Having in mind the defects of the prior art structures, it is a primary object of the present invention to provide an improved pelican hook which obviates the disadvantages described above and which will not accidentally lock or unlock.

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Another object of the invention is to provide an improved pelican hook which may be readily and quickly locked or unlocked with little effort and without the need for heavy or special tools for exerting unusual force to accomplish the looking or unlocking.

A further object of the invention is to provide a pelican book of the above described characteristics which can be uncoupled by hand and without first releasing tension between the coupled elements.

A still further object of the invention is to provide an improved pelican hook of the above described characteristics which is of simple structure, inexpensive to fabricate and which may be generally applied to purposes other than the towing of barges, but, nevertheless, has ease of operation and is highly efficient in use.

The novel features that are considered characteristic of the invention are set forth with particularity in the appended claims. The invention itself, however, both as to its organization and its method of operation, together with additional objects and advantages thereof, will best be understood from the following description of a specific embodiment when read in connection with the accompanying drawing, wherein like reference characters indicate like parts throughout the several figures and in which:

FIG. 1 is an elevational view of a coupling mechanism including a pelican hook according to the present invention, wherein the locked positions of the hook or lock arm and keeper are shown in full lines and'the unlocked positions shown in phantom lines;

7 FIG. 2 is a plan view of the mechanism'shown in FIG. 1;

FIG. 3 is a sectional view taken on the line 3-3 of FIG. 1 and looking in the direction of the arrows, and

FIG. 4 is a sectional view taken on line 4-4 of FIG. 1 and looking in the direction of the arrows.

Referring now more particularly to the drawing, the coupling mechanism of a preferred embodiment of the present invention comprises a turnbuckle bolt 10 connected to a pelican hook including a link 24} connected at one end to the bolt and at the other to a pelican, or hook-shaped, lock anm 30 which is retained in locked position by a keeper link 40 carried by the bolt 10 for securement of a coupling or chain link 50, which may be attached to one barge and the coupling mechanism connected to another barge. The turnbuckle bolt 10 is provided with threads 12 which are opposite to those on a complementary bolt, not shown, and which may be operated by a ratchet mechanism such as fully described in the aforementioned Rumpler patent. The present invention being devoted to the pelican hook structure aside from the turnbuckle and ratchet, no further description will be made of the tensioning ratchet construction.

. At its terminal end, the bolt 10 is provided with a slightly elongated eye 14 which, in use, preferably is disposed substantially in a vertical plane and has an elliptically shaped opening 15 whose major axis is coincidental with the axis a of the bolt, as shown in FIG. 1. Passing through and engaging within the eye 14 of the bolt 10 is one end of the elongated closed link 20 whose other end is engaged in a pivot opening 32 of a pelican hook or lock arm 30. Preferably, the side arms of link 20 extend downwardly to a bend 26 out of the plane of the axis of the bolt 10 and then substantially horizontally or very slightly upwardly toward the other end which passes through the opening 32 of the book 30.

From its pivot end, the hook 30, when in locking position, has an upwardly extending portion 33 and a rearwardly extending portion 36 substantially at right angles to the upwardly extending portion 33 to form a crook 34- providing space above the link 20 for the chain link 50. The bend 26 of the link 20 and crook 34 of the arm 30 enable tension or strain, when applied to the cousnsassn hibits bending or stretching thereof even when the link is formed of soft iron.

The straight portion 36 of the lock arm 3-0 terminates in a free end 37 adapted for passage through the coupling link 50 and formed with a locking. portion 38 that is cooperative with the keeper link 40. The under or inner edge of the arm portion 36 preferably has a generally straight "under or inner edge 35, the free end of which rests on the eye 14 inits locked position and, accordingly, is normally seated in a substantially vertical plane coincident with that of the'bolt eye 14. The locking portion 38 is comprised by a curvature of the upper edge or surface of the free end 37 of the lock arm which is so designed as to freely receive the keeper link 40 but to inhibit accidental movement of the link 40 that would release the .hook arm 30.

Keeper link 40 is pivotally supported in the aperture 15 of the bolt eye 14 in such manner that it may be rotated into a locking position shown in solid lines in FIG. 1 or to an unlocking position as shown in broken lines. The, size of the bolt eye aperture 15 is such that the pelican hook link and the keeper link '40 are free to pivot therein but have substantially no freedom of movement in any direction except the pivotal or rotational movement about axes in the bights of the respective links. The keeper link 40 has an elongated opening 42 which is just long enough to permit engagement therein of the curved locking portion 38 of the free end 37 of the lock arm when the inner edge 35 of the lock arm is resting against the turnbuckle eye 14.

The axis b of the bight of the keeper link 40 is substantially coincident With and transverse to the axis a of the bolt, and the locking portion 38 has'a radius of curvature centered about the bight axis b of the keeper link 40 and approximately equal to the length of the opening 42 in the keeper so that the keeper 40 will swing easily over the portion 38 but will have very little if any clearance that might permit play of the free end 37. The curvature of the locking portion 38 extends from the extreme end of the arm free end 37 to a point over and pastcenter and may terminate in a slight recess- 39. To facilitate movement of the keeper between its locked and unlocked positions, the keeper is provided with an extension 44 which may be formed by hammering, forging, or

by the Welding of an additional piece thereon, and the free end 37 of the hook or arm may be provided with a hole '46 for the removable reception of a safety bolt, pin or the like.

The operation of the present pelican hook should be obvious from the foregoing description. When the chain link '50 extending from one barge is coupled over the" pelican hook or lock arm 30' and the arm swung, to en gage the bolt eye 14, the keeper 40' is freely movable by hand, by exertion of very little force, to ride over the curved edge 38 to lock the hook. Tension may then be applied to the ratchet mechanism connected to the bolt 10 to any degree necessary to rigidify the connection betweenthe barge connected to the bolt and the barge. connected to link 50. The arrangement of the described parts, when thus locked, is such that the strain is substantially in the plane of the axis a of turnbuckle 10.

The turning force exented on arm' 30 by such strain tends to swing the arm 30 away from the. eye 14, and this tension is sufiicient to increase the frictional engagerment between the keeper 40 and the locking edge 38 to Even if sudden changes in the strain ,o'ccur'that would release the pressure on the hook arm 30 tending to pull it away from the terminal eye 14, the frictional engageto slackness in the coupling even with some play in the pivotal connection of keeper 40, there is no possibility of sufficient movement of the keeper longitudinally'ofthe v turnbuckle bolt to disengage the elongated lock arm edges 38 and, therefore, there is no possibility. of accidental dis--. lodgmeut of the keeper from the lock-arm. The curvature of the crook 34 is such as to cam the coupling link 50 toward the book link 20 so that sliding of the link '50 relative to the hook is prevented and tension on the coupling maintains the hook link 20 substantially parallel-with the axis a and provides a direct pull or. tension throughout. 1

When it is desired to uncouple the barges, it is merely necessary to grasp the keeper extension 44 and swing the keeper 40 to the phantom line position shown in "516.1.

Again, this manually effected movement is possible because of the arrangement of the several parts which permits rotation of the keeper when the lock arm is resting against the terminal eye 14. Thus, it is not necessary to strike the keeper with a sledge hammer or other heavy tool in order to dislodge it to unlock the parts. Further, the arrangement wherein the lock arm 30 and the terminal eye 14 are substantially in a vertical plane and maintained therein during the turning of the turnbuckle, places the keeper in a convenient position for manipulation to uncouple the linkage'and the barges.

The linkage parts described herein may be forged, cast,

welded, or otherwise formed of any suitable materialrsuch as soft iron, cast iron or steel. It should further'be apparent that the elements of the linkage are made of suflicient size and cross section to withstand the considerable 7 force involved in the towing of atrain of barges, as described.

Notwithstanding the particular usage described above, it I should 'be apparent that the pelican book may be considerably reduced in size and utilized for linkage problems other than the towing of barges. For example, a chain coupling element may be substituted for the turnbuckle bolt 12 and the described pelican hook thereby appliedto other purposes such as the locking of binder, brake or tow chains, and other fastener or coupling applications.

Although a certain specific embodiment of the invention has been shown and described, it is obvious that many modifications thereof are possible. The invention, there fore, is not to be restricted except insofar as is necessitated by the prior art and by the spirit of the appended claims. 7

' What is claimed is:

l. A pelican hook coupling having a terminal eye, a I closed link connected to the eye, a pelican hook locking.

arm curved to engage with. a chain link and having adjacent one end a pivot aperture receiving said closed link, the other end of said hook arm being free, said hook arm having a length greater than that of said closed link so that the free end portion of said arm overlaps and rests against said eye in locking position, and a keeper link 7 pivotally supported by said eye and being of a length to snugly but freely surround the free end portion of said" hook arm when the latter engages the eye in locking position, the free end portion of said hook arm being provided with an outer arcuate edge'extending to the freeend of said arm, said arcuate edge having a radius of curvature approximately equal to thelength of the opening of said keeper link, and said eye supporting said keeper link for pivotal movement only, whereby to enable substantially free swinging movement of the keeper link to and from locking engagement over said arcuate edge when the lock-5 ing arm engages the eye but inhibiting accidentalmovement of said keeper link from locking position.-

2. A pelican hook coupling having an eye, a closed link pivotally engaged with said eye, a pelican hook. locking arm curved at one end to engage with a link of a coupling chain, said curved end having a pivot opening for receiving said closed link at the end opposite said eye, the other end of said locking arm being free, said hook arm having a length greater than that of said closed link so that the free end portion of said arm overlaps and rests against said eye when in locked position, and a keeper link pivotally received at one end in said eye for turning movement only, said free end portion of the locking arm being provided with an arcuate edge extending to the free end of said arm, in the locked position of said arm said arcuate edge defining an are which is substantially the same as that defined by the end of the keeper link opening during pivotal movement of the keeper link, said keeper link being of a length to snugly but freely surround the free end portion of said hook arm when the latter is engaged with the eye in locked position, whereby to enable substantially free swinging movement of the keeper link into and from locking position over said arcuate edge when the locking arm engages the eye, said arcuate edge having a substantial length and extending over and beyond center relative to the pivotal axis of said keeper link whereby accidental unlocking movement of said link is inhibited.

3. A pelican hook coupling according to claim 2 wherein said arm is provided with a recess at the inner end of said arcuate edge to nest the free end of said keeper link.

4. A pelican hook coupling having an eye, an elongated closed link pivotally engaged with said eye, a curved pelican hook locking arm to engage with a link of a coupling chain, said arm having at one end a pivot opening receiving said closed link at the end opposite said eye, the other end of said locking arm being free and resting against said eye when in locked position, and a keeper link pivotally received in said eye but prevented from substantial movement in any direction with respect to said eye other than swinging movement, said free end of the locking arm being provided with an outer arcuate edge centered in the pivotal axis of the keeper link and having a radius of curvature approximately equal to the length of the opening of said link, whereby to freely receive the keeper link into locking position engaging the arcuate edge of the locking arm and to freely release the keeper link for unlocking the arm,said closed link being bent intermediate its length and said arm having the curve therein adjacent its pivot end so that the coupling chain link will be tensioned against said arm adjacent its pivoted end and said arm and closed link willextend generally parallel to an axis common to said eye and the coupling chain link.

5. In a pelican hook connector for a ratchet coupling, a threaded bolt with a terminal eye having an opening, an elongated closed link having one end passing through said eye opening, a curved pelican hook locking arm having a pivot aperture at one end and through which the other end of said closed link passes, the other end of said pelican hook arm being free for passage through a link of a coupling chain, said hook arm having a length at least equal to that of said closed link so that said free hook end is adapted to engage said eye and be substantially parallel to said closed link when in locking position, and a keeper link having one end passing through said eye opening for pivotal movement only and adapted to surround the free end of said hook arm to retain the latter in locking position, said hook arm having the curve therein adjacent its pivoted end and the inner edge thereof being curved to cam a coupling chain link toward the adjacent end of said closed link, whereby under tension a coupling chain link will be disposed coaxially with said bolt and with said closed link and the major portion of said hook arm generally parallel to such axis so that stress is transmitted longitudinally of said closed link and hook arm.

6. In a pelican hook connector as set forth in claim 5, said eye opening being elongated axially of said bolt and of a size to accommodate both said links for pivotal movement only, said pelican hook arm having a locking portion on the free end thereof which overlaps said eye in locking position and includes an arcuate outer edge formed on an are centered substantially on the pivot axis of said keeper link, said arcuate edge extending from the free end of said hook arm over and past center relative to said keeper link pivot axis and having a radius of curvature approximately equal to the length of the opening in said keeper link.

7. In a pelican hook connector as set forth in claim 6, said keeper link having an extension on its free end to facilitate movement thereof.

8. In a pelican hook connector as set forth in claim 6, said pelican hook arm locking portion having a recess at the inner end of said arcuate edge for nesting said keeper link in locking position and inhibiting accidental unlocking movement of said keeper link.

9. In a pelican hook connector, a terminal eye, an elongated closed link having one end connected to said eye, a curved pelican hook locking arm having a pivot aperture at one end and through which the other end of said closed link passes, the other end of said pelican hook arm being free for passage through a link of a coupling chain and adapted to engage said eye when in locking position, and a keeper link having one end passing through said eye opening and adapted to surround the free end of said hook arm to retain the latter in locking position, said eye opening being of a size to accommodate said keeper link for pivotal movement only, said pelican hook arm having a locking portion on the free end thereof including an armate outer edge formed on an arc centered substantially on the pivot axis of said keeper link, said arcuate edge extending from the free end of said hook arm over and past center relative to said keeper link pivot axis and having a radius of curvature approximately equal to the length of the opening in said keeper link, said closed link being bent intermediate its ends to diverge at said eye from a straight line between said eye and said hook pivot and extend generally parallel but slightly inclined toward said axis at the .end connected to said hook'arm, the inner edge of said hook arm being curved to cam a coupling chain link toward said closed link and the curvature of said hook arm and said closed link being such as to freely accommodate a couplin chain link therebetween while precluding wide diver ence of said connector in locked position.

10. In a pelican hook connector as set forth in claim 9, said closed link being provided with a brace connected to the sides of the link at said intermediate bent portion and said brace being formed with a corresponding bend.

11. In .a pelican hook connector for a ratchet coupling,

a bolt having a threaded shank and a terminal eye with 7 an opening elongated axially of said bolt shank, an elongated closed link having one end passing through said eye opening, a curved pelican hook locking arm having a'pivot aperture at one end and through which the other end of said closed link passes, the other end of said pelican hook arm being free for passage through a link of a coupling chain and adapted to engage said eye when in looking position, and a keeper link having one end passing through said eye opening and adapted to surround the free end of said hook arm to retain the latter in looking position, said closed link and said keeper link passing through said eye in side-by-side relation with said closed link at the terminal end of said opening and said keeper link at the shank end of said opening, said eye opening being of a size to accommodate said links for pivotal movement only, said pelican hook arm having a locking portion on the free end thereof including an arcuate outer edge formed on an are centered substantially on the pivot axis of said keeper link, said arcuate edge extending from the free end of said hook arm over and 'past center relative to said keeper link pivot axis and having a radius of curvature approximately equal to the length of the opening in said keeper link, and said closed link being bent intermediate its ends to diverge at said eye from said axis and extend generally parallel but slightly inclined toward said therebetween while precluding wide divergence of said connector in locked position, said closed link being provided witha brace connected to the sidesof the link at said intermediate bent portion and said brace being formed with a corresponding bend.

12. In a pelican hook connector as set forth in claim 6, said pelican hook having an aperture in its free'end for reception of a pin tosecure said keeper link in locking 7 position.

13. In a coupling connector as set forth in claim 9, said keeper link having anextension on its free end to facilitate movement thereof.

14. In a coupling connector as set forth in claim 9, said pelican hook arm locking portion having a recess at the inner end of said arcuate edge for nesting said keeper link in locking position and inhibiting accidental unlocking movement of said keeper link.

15. In a pelican hook connector as set forth in claim 9,

said pelican hook having an' aperture in itsfree end for reception of a pin to secure said keeper link in locking position. t f

References Cited in the file of this patent UNITED STATESPATENTS 1,643,881 1,761,648 Thomas June 3,1930 1,971,472 Wolf Aug. 28, 1934 2,198,181 Rumpler Apr. 23, 1940 2,616,716 Annis Nov. 4, 1952 2,648,881 Devonshire Aug.'18, 1953 FOREIGN PATENTS 550,570 Belgium Sept. 15, 1956 566,900 Canada Dec. 2, 1958 132,359 Great Britain Sept. 15,1919 161,251

. Great Britain Apr. 4, 1921 Ellis a Septa2 7, 1927 

